Improvement in grinding-mills



UNITED STATES PATENT GEEICE.

CHARLES A. HARPER, OF BURLINGTON, NEW JERSEY.

IMPROVEMENT IN GRlNDlNG-MILLS.

Specification forming part of Letters Patent No. l76,527, dated April25, 1876; application filed July 31, 1875.

To all lwhom it may concern Be it known that I, UHARLEs A. HARPER, ofBurlington, in the county of Burlington and State of New Jersey, haveinvented a new and useful Improvement on Grinding- Mills, of which thefollowing is a specification This invention relates especially toimprovements Ina-de on my Hour-mill patented on the 4th day of March, A.D. 1873, No.136,508.

In the annexed drawings, making part of this specification, Figure 1 isa vertical 1ongitudinal section. Fig. 2 is a'horizontal section. Fig. 3is a transversel section of the hopper. t

The same letters are employed in all the figures in the designation ofidentical parts.

The mill is inclosed in a tight case, A, having on top of ita hopper, B,from4 which the grain is fed to the mill. In order -to give a moreperfect adjustment to the feed two Acurved plates, B1 B2, are secured tothe ends of the hopper by set-nuts and slots, sothat they may beindependently adjusted.

C is a short axle, having both ends supported in bearings, and its innerend bearing against a plate, D, adjusted and held by them by nut D". Itis driven'by a crank or pulley, and has upon its outer end a spurwheel,communicating motion to the ily-wheel shaft.

The mill consists of the concave bed E, rigidly secured to the casing,and a runner, F, convex on its face to fit the concavity ot' the bed.rIhe grain is ground when fed from Y the hopper into the space betweenthe bed and runner. In order to relieve the surfaces from friction therunner F is loosely attached on the shaft., not being keyed to it, butsecured by a pin,F/, which allows it to oscillate on the shaft, and thuspermits small stones or other hard substances to pass through the millwithout breaking it. The space between the bed and runner may beregulated by loosening or tightening the thumb-nuts D.

The shaft Gr carries a y-wheel, H, formed by arms and adjustableweights, and has on one side a projection for giving motion to theshaking screen I, which swings on straps I I', a pin, K, on the shakerencountering the projection G. A spring (not shown) brings back theshaker. The line Hour falls from the shaker into a drawer, L, while theoft'al passes over the end of the screenY and falls upon a slide, M,conducting it into a lower drawer or other receptacle.

As the piu F engages a recess in the back of the runner it will causethe latter to revolve with the shaft; at the same time ythe shaft,havlng bearings at both ends, may be moved longitudinally by theadjustable plate D and thumb-nuts D', to regulate the space between thesurfaces for high or low grinding.

The adjustable weights H H may be set nearer to or farther from thecenter, so as to regulate the momentum of the ily-wheel according to thefeed and character of grain passing through the mill.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. The combination, with the bed E, of the runner F, swung loosely on a.longitudinallyadjustable shaft, having bearings at both ends, andcarried by the pin F', engaging a groove in the back of the runner,substantially as sct forth.

2. In combination with the mill E F and hopperB, the independentlyadjustable curved plates B1 B2, substantially as set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

C. A. HARPER.Y Witnesses: v

LEMUEL C. REEVES, HOWARD D. LE ROY.

